I just saw it recently, I'm trying to figure what was left out from the books -- not that it matters, it was brilliant!. They did as much as they could for 2+ hours. It's been forever since I read the 6th though (read it after Midnight the day it came out).
I'm a little disappointed they left out Snape's class entirely. Wasn't it supposed to be a big shock to think Dumbledore finally let Snape have what he desired, teaching Defense Against the Dark arts?. Only for him to off Dumbledore at the end.
They also left out -why- Snape was the Half Blood Prince. He just basically threw out "Yes, _I_ am the Half Blood Prince!" at the end to Potter with no background. I think Snape's history really humanized him in the books, which made me question his true intentions for killing Dumbledore before people started figuring out he was actually good and redeeming himself.
Okay. That's coming from someone who's favourite character is Snape from the entire series, for whatever reason, so feel free to ignore me. I bawled at Snape's death in the 7th book and didn't shed a single tear when Harry was supposedly "walking to his death".
Also, Richard Harris WAS Dumbledore. Period. The way he talked was educated and wise with a cute sense of humour, exactly what I pictured him as from the books with the lemon drops. This imposter that took his place since the 3rd movie was finally tolerable in the 6th, but he seemed like a skyhigh hippie the moment he showed up on screen for me.
Anyone else surprised how aged Alan Rickman looked in this movie?. It's to be expected, but I was shocked!. Dunno why. I was really happy with the way he portrayed his emotions when he killed Dumbledore in the end, I think it was the only time you really saw his character "break" in a subtle way.
Edit: I waited for Snape to yell "DON'T. CALL. ME. COWARD!." at the end but he never did, did he?.